Detecting device



Nov. 2, 1954 H. LAETARI DETECTING DEVICE Filed Nov. 24, 1952 2Sheets-Sheet l his/WW LAETAR/ 57 fl/S 4770475456 NOV. 2, 1954 ET R I2,692,987

DETECTING DEVICE Filed Nov. 24, 1952 2 Sheets-Sheet 2 F .2 F a 6e 35 754 a2 25 75 59 I i If I I, 57 4 Wu FM United States Patent 6 i DETECTINGDEVECE Henry Laetari, Los Angeles, Calif, assignor to RobertsManufacturing (30., Los Angeles, Calif a corporation of CaliforniaApplication November 24, 1952, Serial No. 322,240

11 Claims. (Cl. 1-102) This invention relates to a detecting devicewhich can be used in conjunction with an apparatus for insertingfasteners in a mounting strip to detect the absence of fasteners fromsaid mounting strip after the apparatus has operated upon said strip toinsert said fasteners therein, said detecting device being designed tode-energize the apparatus to permit the defective strip to be eitherremoved from the apparatus for recirculation therethrough, or to bereturned to a position wherein the missing rasteners can be inserted inthe mounting strip.

As previously indicated, the present invention is designed to beutilized in conjunction with a fastener inserting apparatus and will bedescribed as associated with a fastener inserting apparatus of thecharacter of that more particularly described in copending application,Serial No. 263,096, filed December 24, 1951, now Patent No. 2,669,714granted February 23, 1954, by Newcomb et al., entitled Method andApparatus for Producing Qarpet Retaining Strip. However, although thedetecting device is described as utilized in conjunction with thespecific apparatus and designed to coact therewith, it is obvious thatthe principles of the invention can be utilized with apparatus of amarkedly different character from that disclosed in the previouslyreferred to application.

The primary function of the apparatus with which the device of theinvention is associated is the insertion of a plurality of fasteners ina mounting strip, the fasteners normally projecting a substantialdistance beyond one face of the strip to permit the mounting strip andits associated fasteners to be utilized in retaining flexible floorcoverings such as rugs or carpets in predetermined position on thefloors of rooms or other enclosures. During 1e passage of the mountingstrip through the apparatus, the fasteners are driven into the mountingstrip at predetermined intervals, the fasteners being fed to the stripby fastener feeding means which occasionally fails to feed a fastener tothe face of the strip at the predetermined time which results in ahiatus or gap existing in the row or rows of fasteners which arenormally found in the strip after its passage through the apparatus.Since the strips pass through the apparatus at relatively high speeds,visual detection of the absence of one or more fasteners from the largenumber of fasteners driven into the strip is relatively difficult and itwould be extremely undesirable to provide prospective users with amounting strip which was lacking the predetermined number of fasteners.

It is, therefore, an object of the invention to provide a detectingdevice which will automatically determine the absence of one or morefasteners from the mounting strip after the mounting strip has passedthrough the fastener inserting stage of the apparatus, said deviceincorporating means for indicating to the operator of the apparatus thatan imperfect article has been produced by the machine which is lackingin the requisite number of fasteners.

As the mounting strips are fed through the apparatus with which thedevice of the invention is associated, it occasionally happens that agap exists between adjacent ends of mounting strips being conveyedthrough the apparatus and, due to the gap between the mounting strips,the detecting device of the invention would be caused to functionbecause the detecting device would detect no fasteners in the gapbetween adjacent ends of the two strips. Another object of the inventionis the provision, in a device of the aforementioned character, of meanswhich will temporarily inactivate the detecting device 2,692,987Fatented Nov. 2, 1954 when the absence of a mounting strip from theapparatus is discerned, or when a gap between adjacent ends of themounting strips is perceived.

To enable the detecting device to function for its intended purpose,there is provided therein fastener detecting means which detects thepresence of fasteners in the mounting strip and is responsive to theabsence of one or more fasteners therefrom, said fastener detectingmeans being adapted, when the absence of one or more fasteners isdetermined thereby, to energize the device to tie-activate the apparatuswith which it is associated so that the defective strip may be removedfrom the apparatus or recirculated therethrough.

Also provided in the device of the invention is strip detecting meanswhich detects the presence of a strip in the apparatus and which isresponsive to the absence of a strip at a predetermined point in theapparatus so that when the absence of a strip at the predetermined pointis detected, the strip detecting means will operate to prevent thefastener detecting means from energizing the device to cause thetie-activation of the apparatus.

When the fastener feeding means fails to function properly, it isusually due to a blocking of the feeding means which results in thefailure of the apparatus to insert fasteners in the strip during itspassage through the apparatus. if the operation of the apparatus werecontinued, it is obvious that a large number of fasteners would not beinserted in the mounting strip in the predetermined sequence. Therefore,there is provided in the device of the invention de-energization meansresponsive to the activation of the fastener detecting means by theabsence of one or more fasteners from the strip which will immediately,upon the detection of such absence of one or more fasteners,tie-energize the entire apparatus so that the strip cannot be fedcompletely through the machine when the fastener feeding means is notfunctioning properly. In this manner, waste of time is eliminated sincethe defect is rendered apparent immediately by the cessation ofoperation of the apparatus with which the device of the invention isassociated.

In the particular application with which the device of the invention isdisclosed, the apparatus is designed to drive a plurality of fastenersinto the strip in two rows, the fasteners in each row being spaced anequal distance from each other. It is a further object of the inventionto provide fastener detecting means responsive to the absence of one ormore fasteners from either of the rows of fasteners in the mountingstrip. Furthermore, the fastener detecting means of the invention is soconstructed that before one of the fasteners in either of the rows isdisengaged the succeeding fastener in either of the rows will be engagedto prevent the inadvertent energization of the device by the detectionof the gap between adjacent fasteners rather than the gap created by theabsence of one or more fasteners.

Other objects and advantages of the invention will be apparent from thefollowing specification and the accompanying drawings which are for thepurpose of illustration only and in which:

Fig. 1 is a perspective view showing the device of the inventionincorporated in a fastener driving and inserting apparatus;

Fig. 2 is a transverse, sectional view taken on the broken line 2-4 ofFig. 1;

Fig. 3 is a View similar to Fig. 2 showing the operating portions of thedevice in different positions from those shown in Fig. 2;

Fig. 4 is a front elevational view of the device taken from the brokenline 4-4 of Fig. 2;

Fig. 5 is a transverse sectional view taken on the broken line 55 ofFig. 2; and

Fig. 6 is a fragmentary view taken from the broken line 66 of Fig. 5.

Referring to the drawings, and particularly to Fig. 1 thereof, there isshown a detecting device 10 constructed in accordance with the inventionand utilized in conjunction with a fastener driving or insertingapparatus 11. The fastener inserting apparatus 11 includes a frame 12which has mounted thereupon fastener driving and feeding means 13 forfeeding and driving fasteners 14 into an elongated mounting strip 15. Asbest shown in F1gs. 1-3, the fasteners 14 are arranged in longitudinallyoriented, laterally spaced rows 16 and 17 and the mounting strip or base15 is longitudinally translated through the apparatus 11 on an elongatedbed, indicated genorally at 18, by means of conveyor means indicatedgenerally at 20. Although the strip 15 is described as longitudinallytranslated through the apparatus 11, it could, of course, be translatedlaterally if the apparatus 11 so provided. The apparatus 11 is driven bya motor 21, the moving portions thereof being connected to said motor bymeans of a clutch 22 connected to a transmission shaft 23. Other detailsof construction of the apparatus 11, per so, will not be discussed indetail herein and reference is made to the above referred to copendingapplication for a more, detailed description and discussion of theoperation and structure of the apparatus.

The detecting device, is incorporated in a housing 25 which is mountedon a bed plate, 26 secured to the frame 12 of the apparatus 11.Therefore, as best shown in Fig. 1 of, the drawings, the detectingdevice 10 is disposed adjacent the bed 18 of the apparatus 11 upon whichthe mounting strip 15 is longitudinally translated by the conveyor meansduring its passage through the apparatus 11 to facilitate the detectionof the absence of fasteners 14 from the rows 16 and 17 of fasteners notinserted in the mounting strip 15 by the fastener feeding and insertingmeans 13 of the apparatus 11. It will be noted that the housing of thedevice 10 is longitudinally spaced from the fastener feeding andinserting means 13 of the apparatus 11.

In order to detect the absence of one or more fasteners 14 from themounting strip 15, fastener detecting means 27 are provided, as bestshown in Figs. 25 of the drawings, said fastener detecting means 27being constituted by elongated fingersor bars 29 and 30 mounted upon theextreme outer ends of arms 31 and 32. The elongated bar 29 engages thesuccessive fasteners 14 of the row 16 of fasteners in the mounting strip15, while the elongated bar 30 engages the fasteners 14. in the row 17of fasteners in the mounting strip 15.

The elongated bars 29 and 30 are designed to span the distance betweentwo fasteners in a row of fasteners, asbest shown in Fig. 4 of thedrawings. Therefore, as either of the bars 29 or 30 loses contact with afastener 14 in the row, or shortly prior thereto, it engages thesubsequent fastener in said row, preventing the bar from being movedupwardly, in a manner to be described in greater detail below, toindicate the absence of one ormore fasteners from the row with which itis engaged. The ends of the arms 31 and 32 are rotatably mounted on acommon pivot pin 35 which extends through the housing. 25. Mounted inthe housing 25 below the arms 31 and 32, respectively, are push rods 37and 38. said push rods being disposed in bores 39 and 40, respectively,in the housing 25 and having their lower ends engaged by compressionsprings 41 and 4-2 which tend to bias them upwardly into engagement withthe arms 31 and 32. The push rods 37 and 38 thus serve to move theelongated fingers or bars 29 and. 30 into a first position in which thebars engage successive fasteners 14 in the rows 16 and 17 of thefasteners in the mounting strip 15, as best shown in Fig. 2 of thedrawings. However, when the absence of a fastener 14 occurs due to thefailure of the feeding and inserting means 13 of the apparatus 11 toinsert a fastener in predetermined order in the rows of fasteners 16 or17, the appropriate finger 29 or 30 is moved upwardly into a secondposition, as best shown in Fig. 3 of the drawing wherein the finger 29has been moved upwardly by the action of the push rod 37 and thecompression, spring 41 as applied to the elongated arm 31 to cause saidarm to rotate about the pivot 35 and carry the finger 29 upwardly intothe gap created by the absence of a fastener 14 in the row 16 offasteners in the mounting strip 15. It should be noticed once again thatthe lengths of the fingers or bars 29 and 30 of the fastener detectingmeans 27 are sufficient to span the distance between two adjacentfasteners 14 in a row of fasteners, but are not sufficiently long toprevent their being moved upwardly into the gap caused by the absence of,one or more fasteners in a particular row of fasteners.

The fastener detecting means 2.7. of the detecting device 10 constitutesthe first detecting means of the, invention and is disposed at a firststation with respect to the bed 18 of the apparatus 11. This firststation is one below the plane. of. movement of. the strip 15.

bars 29 and 30 are formed in the shape of inclined planes,

as best shown in Figs. 24, so that when the first. fasteners 14 of a rowof fasteners engage the ends 44 of the bars in their normal passagethrough the apparatus 11, the fasteners will not be wedged thereagainstbut will slide on the inclined planes-to cause the bars 29 and 30 to bedeflected downwardly to cause said bars to assume their first fastenerengaging positions.

The opposite ends of the fingers or bars 29' and 30 are also providedwith inclined-planes at 45 so that; when a mounting strip 15' isre-inserted from the delivery end of the bed-18 into the apparatus 11'to permit the apparatus to insert fasteners'which have been missedduring the initial passage of the mounting-strip 15' through theapparatus, the fingers or bars 29 and 30 will have the inclined planesattheir ends- 45 engage the lower most ends of the fasteners 14 to causethe bars 29 and 30 to ride downwardly-with respect to the fasteners 14and to prevent the wedging of the ends of the bars against the fastenersas the mounting strip 15 is fed into the bed 18 of the apparatus 11.

Incorporated in the housing 25 of the device 119 and constituting aportion of said device is'an apparatus deenergization means 48, said"apparatus de-energization means 48 being responsive to the detection bythe bars or fingers 29and 30 of the absence of one or more fasteners 14from the mounting strip 15, inthe above disclosedand discussed manner.The portion of the apparatus deenergization means 48 included in thehousing 25 ofthe detecting device 10 includes an elongated lever arm 50,said arm being pivotally mounted intermediate its opposite ends on thepivot pin 35 and being disposedbetween the elongated arms 31 and 32which mount the fingers 29 and 31) of the fastener detecting means 27.The elongated lever arm 50, thus constitutes the release means of thedeenergization means 48 and is actuable by the elongated arms 31 and 32of the fastener detecting means 27 by means of a release pin 53 which istransversely secured in one end of the elongated lever arm 50 andengageable by the upper edges of either or both of the elongated arms31and 32 of the fastener detecting means 27.

As best shown in Fig. 4 of the drawings, the release pin 53 extendslaterally of the one end of the elongated lever arm 50in which it ismounted and spans the upper edges of the elongated arms 31 and 32.Therefore, as best shown in Fig. 3 of the drawings, when one or theother of the arms moves upwardly, in this particular instance theelongated arm 31 being shown in the second position in which the absenceof a fastener 14 is detected, the upper edge of the elongated armengages the transversely oriented release pin 53 to urge the one end ofthe elongated lever arm 50in an upward direction.

A compression spring 55 is provided to urge the 61011. gated lever arm50 downwardly and has one end seated on the upper edge. of said leverarm and its other end seated in a cavity provided in the interior of thehousing 25. Thus, when the finger 31 is returned, in a manner to bedescribed in greater detail below, to the first fastener detectingposition, the spring 55 biases the :rlongated arm 50 downwardly into itslowermost posi- The other end of the elongated lever arm 50 constitutesa latch portion 57 and is engageable with an annular shoulder 60provided on an elongated rod 61 which constitutes another portion of theapparatus de-energizatron means of the device. Mounted on the rod 61ex.- ternally of the housing 25 andhaving its opposite ends seated oncollars 63 and 64 is a compression spring 65. The rod 61 can-move freelythrough the collar 63 but the collar 64 isfixedly secured to theperiphery of the. rod 61. The rod 61, as best shown in Fig. 5 of thedraw.- ngs, 1s longitudinally shiftable in a bore 67 in the housmg bymeans of the spring 65 whichv is. compressed between the collar 64 andthe collar 63' when the latch portion 57 of the elongated lever arm 50engages the annular shoulder 60 on the rod 61.

Therefore, when one of the elongated arms 31 and 32 of the fastenerdetecting means 27 is moved upward 1y by its associated push rod, due tothe absence of one or more fasteners 14 from the mounting strip 15, andengages the transversely oriented release pin 53 in the elongated leverarm 50 to pivot the lever arm 50 about the pin 35 and move the latchportion 57 of the elongated lever arm 50 downwardly out of engagementwith the shoulder 60 on the elongated rod 61, the spring 65 urges therod 61 to the right in the direction of the arrow 69 of Fig. l tode-energize the apparatus 11 in a manner which will be described ingreater detail below.

Supported upon and constituting a portion of the housing 25 is anauxiliary cylindrical housing 70, the housing 70 providing a support andpartial enclosure for strip detecting means 75. Supported in the housing70 is an elongated arm 77 which constitutes a portion of the stripdetecting means 75 and has mounted in its outermost end the threadedshank 78 of a follower 80. The follower 80 is of frusto-conicalconfiguration and its lower end is engageable with the upper surface ofthe mounting strip 15, as best shown in Figs. 2 and 3 of the draw ings.The inner end of the elongated arm 77 is mounted for rotation with andupon an elongated latch pin 82 which is mounted centrally of thecylindrical housing 70 by means of a bore 83 in the upper end thereofand a bore 84 in the main housing 25. The cylindrical housing 70includes an external shell 86 which is provided with a Vertical slot 85through which the elongated arm 77 projects, the shell 86 beingrotatable with the arm 77 when it rotates with and upon the latch pin82. Encompassing the periphery of the latch pin 82 and seated betweenthe upper edge of the arm 77 and the inside wall of the top of thehousing 70 is a compression spring 87, said spring tending to bias thearm 7'7 and its associated lock pin 82 downwardly into the positionshown in dotted lines at 89 in Fig. 2 of the drawings wherein the lowerend of the lock pin 82 engages the upper edge of the elongated lever arm50 and wherein the frusto-conical cam follower 80 is disposed in theposition shown by dotted lines at 90 in Fig. 2 of the drawings.

Provided in the base of the housing 70 is an annular cam 91, said cambeing engageable by the lower edge of the elongated arm '77 and serving,when the arm 77 is rotated on and with the lock pin 82 in the shell 86,to raise the arm 77 and its associated follower 80 to permit thefollower 80 to engage the upper surface of the mounting strip which isbeing longitudinally translated along the bed 18 of the apparatus 11.

The basic function of the strip detecting device 75 is to prevent theactuation of the elongated lever arm 50 by either one of the arms 31 or32 of the fastener detecting means 27 due to the absence of a mountingstrip 15 at the station where the fastened detecting means 27 operates.When a mounting strip 15 is translated longitudinally on the bed 18 ofthe apparatus 11, the leading end thereof engages the frusto-conical camfollower 80 of the strip detecting means '75. The elongated arm '77 ofthe strip detecting means 75 is, at the time of contact with the leadingend of the strip 15, disposed in the dotted line position shown in Fig.5 of the drawings. The position of the arm 77 shown in full lines inFig. 5 of the drawings constitutes the first strip engaging position ofthe arm and the arm is maintained in this position by means of a tensionspring 94 which is connected between said arm and the bed 18 of theapparatus 11. When the arm 77 is disposed in the first strip engagingposition shown in Fig. 5 of the drawings, the follower 80 mountedthereupon is disposed in a first, lowermost posltion shown at the dottedlines 90 in Fig. 2 of the drawings.

Therefore, the longitudinal movement of the leading end of the stripcauses it to engage the follower 80 and to carry the follower 80 and itsassociated arm 77 n an are between the first strip engaging pos1t1onshown in Fig. 5 of the drawings and a second, temporary position of thearm 77 shown in dotted lines in said figure, against the tension of thespring 94. As the arm 77 is carried in the above described arc, thelower edge thereof engages the upper surface of the cam 91 and the arm77 is carried upwardly on the cam 91 to raise the follower 80 from thefirst, lowermost position shown at 90 in Fig. 2 to a second, uppermostpost1on 1n wh ch it may engage the upper surface of the mounting strip15.

As shown in Figs. 2 and 3, the follower is urged in the direction ofmovement of the strip 15 through the apparatus 11, as indicated by thearrow 95 in Fig. 5 of the drawings.

Although the action of the cam 91 is largely responsible for the upwardmovement of the follower and its associated arm 77, the frusto-conicalshape of the follower 80 prevents the follower from binding upon theleading end of the strip 15 and serves, also, to urge it upwardly toaugment the upward movement imparted thereto by the lifting action ofthe cam 91. When the follower 80 has been urged into the second positionshown in dotted lines in Fig. 5 of the drawings by the leading end ofthe strip 15, it has also been raised by the cam 91 and the arm 77 intothe second uppermost position shown in full lines in Fig. l of thedrawings where it engages the upper end of the strip. When suchengagement occurs, the tension spring 94 snaps the arm 77 back into thefirst position shown in full lines in Fig. 5. When so disposed, thefollower 80 is located at a station immediately in advance of thefastener detecting means 27 so that the absence of a strip 15 from thebed 18 will permit the follower 80 to drop into its first, lowermostposition to prevent the energization of the fastener detecting means 27.During the movement of the strip 15 through the apparatus 11, the arm 77and the follower 80 are thus maintained, respectively, in the firstposition and the second, uppermost position.

Thus, should a gap occur between the ends of strips 15 being fed throughthe apparatus 11, as best shown in Fig. l of the drawings, when thetrailing end of the strip 15 reaches the follower 80 in its first andsecond uppermost positions, the follower 80 will drop from engagementwith the upper surface of the strip 15 so that it will move from itssecond, uppermost strip contacting position into the first lowermostposition indicated by the dotted lines in Fig. 2 of the drawings.

When this occurs, the downward movement of the arm 77 is accompanied bydownward movement of the locking pin 82 which then rides into engagementwith the upper edge of the elongated lever arm 50. However, when thetrailing edge of the strip 15 has passed over the fingers or bars 29 and30, the normal tendency thereof is to move upwardly since they are nolonger in contact with fasteners 14 mounted in said strip. The lockingpin 82eifectively prevents such upward movement of the fingers or bars29 and 30 by restraining the elongated lever 50 from upward movement,through its contact with the upper edge of the lever 50 and theengagement of the release pin 53 mounted in said lever with the upperedges of the arms 31 and 32 upon which the fingers 29 and 30 aresupported.

Therefore, the strip detecting means 75 prevents the inadvertentactuation of the apparatus de-energization means 48 of the device when astrip 15 is not positioned with its fasteners incorporated therein atthe point along the bed at which the fastener detecting means 27 islocated. It should be noted in passing that the strip detecting means 75is positioned at a second station with respect to the bed 18 whichoverlies the fastener detecting means 27 and the strip 15 as it islongitudinally translated through the apparatus 11. However, once thefollowing strip 15 engages the follower 80 of the strip detecting means75 and the follower 80 has been returned to its first position shown infull lines in Fig. 5 of the drawings, the locking pin 82 is movedupwardly into its second, uppermost position in conjunction with the arm77 and the follower 80, thus freeing the upper edge of the locking lever50 for movement by the arms 31 and 32 of the fingers 29 and 30 of thefastener detecting means 27.

As previously indicated, when the absence of one or more fasteners isdetected by the fingers or bars 29 or 30 of the fastener detecting means27, the latch portion 57 of the lever arm 50 is moved downwardly torelease the annular shoulder 60 on the rod 61 permitting the rod 61 tobe urged to the right, as shown in Fig. l of the drawings, by the actionof the compression spring 65. The elongated rod 61 has the end oppositeto that mounted in the housing 25 mounted in an end block 97 on theframe 12 of the apparatus 11. The end of the rod 61 adjacent the endblock 97 is connected to a substantially T-shaped lever 98 which ispivotally mounted upon the frame 12 of the apparatus at 99 by one legthereof, the other leg 100 engaging one end of a pivotally mountedhandle 102 which has secured intermediate its ends a 7 verticallydisposed. push rod 103.. The lowermostend of the push rod103 is securedto a bellcrank 105, said bellcrank. being connected to the throw-outlever 106 associated with the clutch 22. Thus, when the rod. 61.

which constitutes a portion of the de-energization means of the device10 is shifted to the right, as best shown in. Fig. lof the drawings, thelever 98 is pivotedv at 99 upon the end of the rod causingthe other arm100 thereof to be raised against the end ofthe handle 102. The upwardpivotal movement of the handle 102 causes the concomitant verticaltranslation of the push rod 103, moving. the bellcrank 105 in an arc torotate the. throw-out lever 106 to throw out the clutch and. thus severthe drivingdniven relationship between the motor 21 and the shaft Inthis manner, the detection of the absence of one or more fasteners froma mounting strip by the fastener detecting means 27 'of. the device 10'automatically deenergizes the apparatus ll through the de-energizationmeans'of the device 10 and immediately causes the cessation of thelongitudinal translation of the strip 15 through the apparatus 11.

After the device 10 has indicated theabsence of one or more fasteners 14from the strip 15 by shutting down the apparatus 11, the strip 15. can.be removed from the bed 18 and recirculated therethrough at a later timewith a plurality of similarly defective strips or, it can be refed ontothe bed 18 to permit thernissing fastener to be in.- serted therein. Toinitiate the operation of the apparatus 11 after the detection of animperfect strip 15, the handle 102 is depressed. When this occurs, therod 103 moves downwardly, the bellcrank 105 is rotated and the throwoutlever 106. is pivoted to throw in the clutch 22 to establish adriving-driven.relationship between. the motor 21:.and the shaft 23. Thedownward movement of the handle 102 causes the concomitant downwardmovement of the other portion of the crossbar 100 of the T-shaped lever98 which pivots at 99 and causes the longitudinal translation of theelongated rod 61 to the left, as best shown in Fig. l of the drawings;When the longitudinal translation of the'rod to the left occurs, thespring 65 is compressed between the collars 63. and 64 and the. shoul-.der 60of the'rod 61 is brought into registry with the latchportion 57 ofthe elongated lever arm 50. Due to the action of the spring 65', thelatch portion 51 is urged upwardly into engagement with the shoulder 60and the downward movement of the pin 53 inthe end of the lever 50 causesthe concomitant downward movement of. the arms 31 and 32 upon which thebars 29 and of the fastener detectingmeans 27 are supported. In thismanner, the device 10 and the apparatus 11 are simultaneously energizedand the device 10 and apparatus 11 are once again ready to operate uponthe mounting; strip 15 passing through the apparatus 11.

There is provided by the invention. a detecting device which is designedto automatically ascertain the absence of one or more fasteners fromamounting'strip passing through a fastener securing apparatus. Alsoincorporated in the detecting device is a fastener detecting means whichdiscerns the absence of one or more fasteners from the strip and a stripdetecting means which discerns the absence of a strip-from the bed ofthe apparatus with which the device is associated or the existence of agap between a. leading'and following, strip. Incorporated in the stripdetecting means is lock means designed toprevent the actuation of thefastener detecting means when such actuation would becaused by theabsence of a strip from the apparatus.

Also found in the device of the invention is apparatus de-energization'means actuable by the fastener detecting means upon the detection bysaid fastener detecting means of the absence of one or: more fastenersfrom a strip. Otheradvantages and. advances ofthe invention and'thedevice embodying said invention can be found by resort to the abovespecification.

I claim as my invention:.

1. In a device for detecting the absence of fasteners from a base stripin which fasteners are normally secured, the combination of firstdetecting means engageable with fasteners in said strip for detectingthe absenceof fasteners from said strip; and second detecting meansplaced ahead of said first detecting means and operativelyengageablewith. said first detecting means for preventing theoperation of saidfirst. detecting means when said. strip is moved beyondsaidseconddetecting means,

2. In adevice for detecting; the. absence of. fasteners from a basestrip in which fasteners are normall'y secured during the movement ofsaid base strip through a fastener inserting apparatus, the combinationofz. first detecting means engageable with fasteners in said strip fordetecting the absence of fasteners from said strip during its move' mentthrough said apparatus, said first detecting means including fingermeans movable into engagement with said fasteners; and second detectingmeans placed ahead of-said' first detecting means and operativelyengageable with said strip for preventing the operation of said firstdetecting means when said strip is moved beyond said second detectingmeans.

3. In a device for detecting the absence of fasteners from a base stripduring the movement. of. said strip through an apparatus which insertsfastenerstherein, the combination of: first detecting means engageablewith fasteners in said stripfor detecting the absence. of fasteners fromsaid strip; second detecting means placed ahead of said first detecting.means and operatively engageable with said strip for preventing theoperation of said first detecting means when said strip is moved beyond.said second detecting means in. said apparatus; and deacuation means forpreventing the operation of said apparatus operable by said firstdetecting means when saidfirst detecting means is operated by theabsence of a fastener from said strip.

4. In a device which is operatively associated with an apparatus forinserting fasteners into a mounting strip to detect the absence of oneor more fasteners from said strip subsequently to the insertion offasteners by said apparatus, the combination of: a bed' for supportingsaid strip during movement through said apparatus; conveyor meansoperatively engageable with said strip for causing the longitudinaltranslation thereof through said apparatus; first detecting meansengageable with fasteners in said strip for detecting the absence of afastener from said strip; and second detecting means disposable inadvance of said first detecting means adjacent. said bed for detectingthe absence of said strip from said bed to prevent the actuation of saidfirst detecting means due to the absence of said strip from said bed.

5. In a device responsive to the absence of fasteners from a fastenermounting base strip, said device being associated with an apparatus forinserting fasteners in said strip, said apparatus including an elongatedstrip supporting bed and conveyor means for longitudinally translatingsaid strip along said bed, the combination of: strip detecting meansmounted adjacent said bed and engageable with said strip for determiningthe presence of said strip on said bed; and fastener detecting meansmounted adjacent said bed and engageable with fasteners in said strip,said fastener detecting means being operatively engageable by said stripdetecting means to prevent the operation of said fastener detectingmeans when said strip detecting means is actuated by the absence of saidstrip from said bed.

6. In a device responsive to'the absence of fasteners from a fastenermounting base strip, said device being associated with an apparatus forinserting fasteners in said strip, said apparatus including an elongatedstrip supporting bed and conveyor means for longitudinally translatingsaid strip along said bed, the combination of: strip detecting meansmounted adjacent said bed and disposable at a first station, said stripdetecting means being engageable with said strip and responsive topassage of said strip beyond said first station; and fastener detectingmeans mounted adjacent saidbed at a second station spaced from saidfirst station, said fastener detecting means being engageable withfasteners in said strip to detect the absence of afastener from saidstrip and being operatively engageable by said strip detecting means toprevent the actuation of said fastener detecting means because of theabsence of a strip from said bed.

7. In a device for detecting the absence of fasteners from a fastenermounting base strip during its movement along the bed of a fastenerinserting apparatus, the combination of: strip detecting means mountedadjacent said bed at a first station, said strip detecting meansincluding a follower engageable with saidstrip and responsive to thecompleted passage of said strip along said bed; and fastener detectingmeans mounted adjacentsaid bed at a second station, said fastenerdetecting means being operativelyengageableby said strip detecting meansto prevent the actuation of said fastener detecting, means due to thecompleted passage of a strip through said apparatus.

8. In a device for detecting the absence of fasteners from a fastenermounting strip during its passage along the bed of a fastener insertingapparatus, the combination of: a housing mounted adjacent said bed;strip detecting means secured in said housing and movable by the passageof a strip along said bed, said strip detecting means including afollower engageable with said strip; fastener detecting means mounted insaid housing including fastener engaging fingers for detecting theabsence of one or more fasteners from said strip; and deactuation meansoperable by said fastener engaging fingers when said fastener engagingfingers detect the absence of one or more of said fasteners from saidstrip to deactuate said apparatus, said deactuation means beingengageable by said strip detecting means to prevent the operation ofsaid deactuation means when said strip detecting means responds to thecompleted passage of a strip through said apparatus.

9. In a device which is operatively associated with an apparatus forinserting fasteners into a mounting strip to detect the absence of oneor more fasteners from said strip subsequently to the insertion offasteners by said apparatus, the combination of: an elongated bed; aconveyor means for translating an elongated mounting strip along saidbed; a strip detector mounted adjacent said bed, said strip detectorincluding an elongated, movable arm and a strip contacting followermounted upon said arm, said arm having fastened thereto latch meansresponsive to movement of said follower in a vertical plane; fastenerdetecting means mounted adjacent said bed and spaced from said stripdetector; and deactuation means operable by said fastener detectingmeans when said fastener detecting means detects the absence of one ormore fasteners from said strip, said latch being movable into engagementwith said deactuation means to prevent the actuation thereof by saidfastener detecting means when said strip detecting means moves out ofcontact with a strip subsequently to the passage of said strip throughsaid apparatus.

10. In a device which is operatively associated with an apparatus forinserting fasteners into a mounting strip to detect the absence of oneor more fasteners from said strip subsequently to the insertion offasteners by said apparatus, the combination of: a bed for receivingsaid strip; conveyor means for conveying said strip along said bed; astrip detector mounted adjacent said bed, said strip detector includinga movable follower operatively connected to a movable lock; a fastenerdetector mounted adjacent said bed in spaced relation with said stripdetector, said fastener detector including fastener engaging fingers forascertaining the absence of one or more fasteners from said strip; andrelease means mounted adjacent said bed in operative relation with saidstrip detector and said'fastener detector, the movement of said stripdetector from a second strip releasing position to a first stripengagingposition causing the movement of said lock out of operativeengagement with said release means to allow actuation thereof by thefastener detector means.

11. In a device designed to detect the absence of fasteners from amounting strip during the translation of said strip through a fastenerdriving apparatus, the combination of: a housing; a strip detectormounted in said housing for longitudinal movement between a stripengaging position and a strip releasing position and for movementbetween a first unlocked position and a second locked position; fastenerdetecting means mounted in said housing for movement between a fastenerengaging position and a fastener absence detection position; and releasemeans operative by said fastener detecting means and engageable by saidstrip detector to prevent the actuation of said release means by saidfastener detecting means when said strip detector detects the absence ofa strip from said apparatus.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,555,596 Miller Sept. 29, 1925 2,616,541 Smith Nov. 4, 1952

